LIGHTNING PROTECTION CIRCUIT

摘要

A surge protection circuit includes a surge protection unit (1) and an interface (2) electrically connected to each other. The surge protection unit (1) includes an internal connection terminal block (11), three varistors (12,13,14), and one discharge tube (15). The three varistors (12,13,14) are electrically connected to the internal connection terminal block (11), where two varistors (13,14) are electrically connected to the discharge tube (15). The discharge tube (15) is also electrically connected to the internal connection terminal block (11) and is grounded. The surge protection circuit can avoid connecting a varistor to the discharge tube in series and reduce a residual voltage of the surge protection circuit.